Method of making gun-sights.



D. GRANT.

METHOD OF MAKING GUN SIGHTS.

APPLICATION FILED AUG.6. 1914.

1,273,770. Patented July 23,1918.

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D. GRANT.

METHOD OF MAKING sun SIGHTS.

APPLICATION FILED AUG-5, I914- ,77 Patented July 23, 1918.

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1 m 11 Fly-9 I 3mm; Zarz'i gilllt a f M 3% UNITED I S AI mTENT OFFICE DAVID GRA T, MIDDLEFIEIiD, coNNnc Iou ASSIGNOR o THE LY'MA'N GUN sIeHT CORPORATION, OF MIDDLEEIELD, CONNECTICUT, A CORPORATION or" CO E TICUT.

'METHOD OF MAnINGGuN-sien'rs',

' Speeifihatiqn of Letters Pat ent. Pa n -Ju y 23,

. Application filed August 6, 1914; Serial No. 855,438.

To all whom itmay concern: v i

Be it known that 1, DAVID GRANT, of Middlefield, in the gcountyof Middlesex and in the State of Connecticut, have invented a certain new'iand useful Improvement in Methods of Making G1 1n-.S,ights, and do hereby declare that the following is a full, clear, and exact description thereof. The muzzle or front sights of fire arms which comprise ahead and a dovetail base by which the si ht is attached to the gun barrel, as heretoforemadewas produced by milling. This operation is slow and, there-, fore, costly. The object of my inventionis to enable these gun sights to be made more rapidly, and, therefore, more economically, 1

and I accomplish such object by die-pressing or shaping, first ;providing.a blank that roughly is T-shaped in cross section. These sights requireto be constructed with the greatest accuracy possible and especially must the dovetail base be madezwith great accuracy for fitting or adaptation of the sight to the transverse retaining groove in" any gun barrel. ,7 It is for this reason and because of the accuracy with which milling may be done, and because of certain practi' cal difficulties inthe way of die-pressing, or stamping out such an article, that there has been no departure from the milling method. The value and importance of my'invention compared with the old milling method of manufacturing these gun sights will be seen, when it is statedthata workman making these sights in accordance with my invention in two hours and thirty-five minutes can.

turn out as many sights as can be made in eighteen days by themillingmethod. Notonly is there this great advantageinrapidity and economy of manufacture, but the sight itself is better by reason of the con-. densation or solidifying of the metal due to the dieing operation and because of the uniformity of the product to a degree not possi-', ble with milling, My invention, therefore,

comprehends an art or process of making gun sights.

In the accompanying drawings Figure 1 is an elevation of a die andwork holder for carrying-out my invention showing sections of the die bed and punch;

Fig. 2 is a similar figure in central cross,- section as taken on the line 2-2 of Figs. 3'

and 4;

Fig. 3 is an .elevationof Fig. l

tioncfor the-reception-of the work; r

will comprise a side elevation;

Fig. 4 is a central horizontal cross-section throughFigs. 1 and 2;

Fig. 5 is a view corresponding to of the die and work holder inthe open posi- Fig. 6 is ahorizontal central. cross-section through-Fig. 5; g r

Fig. 7 is a perspective viewijof a blank adaptedv for the formation, of a gun-sight by means of my invention; ,7 j Fig. 8 is a perspective view of a com:

pleted sightformedfrom such a -blank;,i

Fig. 9 is a view of the muzzle end of a gun barrel and side View of a gun sight mounted thereon; v Fig. 10 a detail view of thediesfor forming the sighttridge.

9 :particularly, is shown a front sight 10 for fire-arms, of thetyp'ewhich is heldin place on the barrel by means of adovetailedtenon.

-or base 11, on the lowerside of thelpart,

serted tightly in a correspondingly shaped. groove 12, in the upper surface of the muzzle end of the barrel of the fire-arm 100. The; sight proper comprises a ridge or eight. head? 13, formed on the upper surface of the sight, block transversely of the dovetailed base or ten on, and therefore longitudinally of the; barrel, since the dovetail 1s fittedcross eviise thereof, as shown in Fig. 9. Asthe sightfr e-., quires to be mounted absolutely centrallyel" the barrel of the fire armor with the sight.

bead in the vertical plane of the airis "orllirie; of aim, and is held by friction in the g'roo ife. in which it isseated, .theutmostdegree of accuracy is necessitated .in shaping and standardizingthe configuration and propor tion of the dovetailed sight base and relative position andconstruction of the sight. bead. The formation ofthesight means of dies present igreatgdifliculties forf the mechanism is required to insure s uch minute" fractional uniformity of the measure be-.

tween angular sides ofthe dovetailedba'se} that the sights taken at random will fitthe grooves of firearms indiscriminately, with;

substantially the same frictional hold at the '7 same point whereby the sight when inserted. to-the same centralposition may beheld I with invariable clutching 'efiect Also the formation of v the angular surfaces ,the

Referring tothe drawings, in Figsiland dovetail involve lateral thrust both upon the dies and the work in one direction only, and is impossible of counteraction by the ordinary devices of power presses.

My appliances for producing this class of work comprise a twopart holder in which the work is clamped and the forming dies 7 are guided and confined, and centralized in action, and the lateral strains of operation rendered reactionary and counter-resistant. The'holder comprises the two parts, 11 and 15, hinged together at one side by means of the respective hinge ears 16 and 17, formed thereon and the hinge pin 18, upon which both parts are swung in the operation of being opened orclosed. In the opposite edge of one-of-the parts ll are hinged the swivel nuts 19, in which are screwed suitable clamping screws :20 adapted to bc swung into slots 21, in the-edge of the opposite part and their heads 22, screwed down firmly thereon to clamp the sections together in the closed position, as shown in Figs. 1 and 3.

Centrally in the section 15, is a recess or seat 23, for the reception of the die or dies for holding the work. In Figs. 5 and (i is shown the die 21, for seating thesight blank in the construction of the sight ridge while Figs. 2 and a, show the dies 30, for holding the blank by means of the sight ridge, in the operation of, shaping the dovetail. These dies are held in their seat by the screws 31 inserted through the bottom of the holder. In the interior face of the said part1?) in the plane of the recess, a groove is formed extending from one edge of the holder to the other parallel with the hinge and-providing separate guide-ways 241 on the respective'sides of the recess 23, for the reception of the respective dies 25, in alinement with each other and the center of the recess. The inner ends of the dies have the configuration of the article to be shaped between them which in Figs. 2 and t is the dovetail of the sight, the dies in such case having ends cut to the angle of the dovetail, as shown. The opposite ends of the dies are cut square with their length, for contact with the punch head and die bed 26 and 27, of a power press, or other mechanism for applying pressure for forcing the dies together and upon the work. The dies for forming the sight ridge, which in cross section comprises a cylindericonnected to the base by a neck, as shown in Fig. 8, will obviously be formed of corresponding shape at the ends which engage the sight or bead but otherwise do not differ in any respect from dies 25 shown in Fig. 2.

In the opposite section 14: of the holder a cavity 28 is provided for seating an anvil or resistance block 29, centrally registering with the seat 23, and adapted to bear upon the sight blank to resist the lateral strain imposed by the die thereon. A set-screw 271 is screwed into the sect-ion of the holder back of the resistance block in engagement therewith and by means of which the block may be forced or clamped tightly in its seat.

A pair of screw threaded studs 32, are screwed into each end of each of the holder sections, with their ends projecting to form adjustable stop elements which by engagement with the punch head 26 and die bed 2-7 of the press serve to gage the space between said parts atthe limit of the stroke of the punch, and to determine the amount of the action of the forming dies as hereinafter fully specified. Set screws 3-3, are provided for securing these stops in position when adjusted by binding action against their sides. In the operation of this mechanism, two distinct actions are involved in connection with the formation of the respective independent features of the sight shown and described, viz., the sight bead, and dove-,

tailed base, but which involve substantially the same procedure. 7

Considering first the formation of the sight bead, the die 2% is placed in the recess 23, and the sight blank .831 is set into the groove 34, in the die, which is of the width to receive it loosely, as shown in Fig. 5, the fiat side of the blank being placed in contact with the die with thesight bead part projecting above the die transversely to the plane and path of movement of the two shaping dies received and guided in the guideways of the holder. 'The ends of the said forming dies which face each other are shaped to conform to the finished shape of the sides of the sight bead, but otherwise do not differ from the representation of the forming dies in Fig. 2, and they are omitted from Fig. 6, which shows the blank in position to form the sight bead, but it will be understood the forming dies operate thereon as described with reference to Figs. 2 and 4t, hereinafter specified. The opposite half or section H of the holder next being closed upon the part 15 and the two sections locked together by the bolts 20, and nuts'l9, and tightly screwed together with the forming dies received in their guide-ways the holder may then be placed upon the press bed as shown in Fig. 1, and the punch-head brought down upon it. It is to be understood that the forming dies prior to the operation of shaping the part and when in contact with the work together register a greater length between their outer ends than the length over all between the ends of the adjustablestop studs, said excess space between the ends of the forming dies representing the amount of movement which the dies are to make to shape the work and which may be determined by the requisite adjustment of the stops, as shownin Fig. 3. The forming dies are passed over the base part of vthe blank until they contact with'the sight ridge, at which point they will remain at rest until pressure is brought to bear upon them to compress and mold the sight ridge int-o the true form of the sight head which is that shown in Figs. & and S, or its configuration after receiving the impact of the dies.

It will be observed that through the provision of suitable clearance space 36 the the sight blank is not held rigidly in its seat in the die 24:, but can readily move vertically therein under the action of the forming dies, thus floating as it may be termed, into the proper position to centralize itself between the respective dies and receive equal pressure and impact from eachand form equal'depths of'cut on the respective sides of the block. In this action, which is of the utmost importance in the standa'rization of the product, the lateral strain on the work is in the direction to force the blank down upon its seat in the holding die and the resistance block is not required to press against the blank in the shaping process, and in the production of this feature of the sight its use can be dispensed with; In

other words since the tendency under the pressure of the bead-forming dies is not to force the metal of the blank toward the holding die 29, the latter need not be present during the action of the dies for forming the bead.

In the operation of forming the dovetailed base of the sight, employing the holding dies 80, between which the finished sightbead is placed lengthwise with respect to the stroke of the forming dies as shown in Fig. 2 and Fig. 4, with a base of the blank in the line of action of the forming dies 25, as shown in Figs. 2 and 4, it is necessary to make use of the resistance block or anvil 29 to oppose the lateral strain on the work by the angularity of the ends of the dies which in operation tend to force the blank in the direction of the opposite part of the holder. With the anvil in place and screwed tightly against the work the forming dies may then be forced upon the blank base to form the dovetailed impressions therein corresponding to the angular ends of the dies, as shown in Fig. 2. In this process the work is enabled to move in its seat by means of the clearance space 37 provided therefor, and centralize itself with reference to the shaping dies and the stops of the holder to insure equal depths of the impressions in the respective sides of the dovetail, and accurate intermediate measurement between them. The stroke of the press should be adjusted to close the punch and press bed silghtly nearer together than the length over all between the ends of the stops in order'to insure the full stroke of the forming dies and eradicate all possibility of lost motion in the 'parts. 'Such slight excess movement of the punch is made possible by the slight corresponding yielding action or springof thepress frame which lacks absolute rigidity and possesses sufficient elasticity for such purpose. 7 The completion of the doveta'il indentations of the base Will result in theproduction of a finished sight base as shown in Fig. 8. Y

The anvil block as. shaped to assist in the production of the dovetail of the base is preferably formed with 'a'cent'ral recess 38, as shown in Figs. 2 and 4, which restricts its bearing to its ends. 7 The resisting effect of the anvil is'required chiefly upon the ends of the base or those portions on the sides of the sight bead andwhich are .of much less thicknessthan the central depth of the block through'the bead. The tendency of. the action ofthe diesis to draw down upon said thin portions and fracture their ends and otherwise distort the blank.- The'counteracting pressure should be directedto said ends and'concentrated thereon and this I efiectually accomplish by relieving or forming a chamber in the central zone or field of the resistance block as 1 shown so that it bears wholly upon the said thin parts of the sight base.

By the use of the holder the lateral strain on the dies is counteracted and their action is confined to a predetermined field while the work is held to the plane of such'action in resistance to lateral strain and centralized between the dies resulting in a finished product superior in quality to milled work and at a vastly reduced cost. The holder with its stop comprises a gage whichmathematically insures the precise and invariable length of stroke of the dies and infinitesimal accuracy and uniformity of the proportions of the stamped parts and their standardization while the provision for the floating or self-centering movement of the work secures the positioning of the sight bead exactly central of the base whereby when it is brought into coincidence with the line of sighting when the sight is driven into its seat in the gun barrel, the frictional hold of the base therein will always be the same in sights indiscriminately selected from a lot, and any sight. produced by the systems can be relied upon to fit perfectly upon any gun barrel which has a sight seat calculated for it, simply as the parts are furnished to the trade, and without further manipulation.

A press of ordinary construction can be used in the practice of my invention and my invention can also be practised in a specially organized machine or press.

Having thus described my invention what I claim is 1. The method of making gun sights comprising a bead and a dovetail attaching base, which consists in taking a blank that is T-shape in cross sect-ion and subjecting it to the action of dies which form the bead and the dovetail attaching base.

2. The method of making gun sights comprising a bead and a dovetail attaching base, which consists in taking a blank that is T- shape in cross section and subjecting it in successive operations to the action of dies which form the bead and the dovetail attaching base, the bead-forming operation being performed first.

3. The method of making gun sights comprising a bead and a dovetail attaching base, which consists in taking a blank that is T- shape in cross section and subjecting it in successive operations to the action of dies which form the bead and the dovetail attaching base, the bead forming operation being performed first, the blank being supported so that it may move under the action of the dies in a direction at right angles to the length of the dovetail.

4. The method of making gun sights comprising a bead and a dovetail attaching base, which consists in taking a blank that is T- shape in cross section and subjecting it to the action of dies which form the bead and the dovetail attaching base, said dies being in pairs and caused to move upon the part of the blank being acted upon simultaneouslv from opposite directions.

5. The method of making gun sights com prising a bead and a dovetail attaching base, which consists in taking a blank that is T- shape in cross section and subjecting it in successive operations to the action of dies which form the bead and the dovetai] attaching base, the bead-forming operation being performed first, said dies being in pairs and caused to move upon the part of the blank being acted upon simultaneously from opposite directions.

In testimony that I claim the foregoing I have hereunto set my hand this twentyeighth day of July, A. D. 1914.

DAVID GRANT.

lVitnesses GEORGE L. BARNES, HAROLD G. BURNHAM.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of I'atents, Washington, D. O. 

